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Full-Text Articles in Diseases

Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo Oct 2012

Dendritic Cells In Hepatitis C Infection: Can They (Help) Win The Battle, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

Infection with hepatitis C virus (HCV) is a public health problem; it establishes a chronic course in ~85% of infected patients and increases their risk for developing liver cirrhosis, hepatocellular carcinoma, and significant extrahepatic manifestations. The mechanisms of HCV persistence remain elusive and are largely related to inefficient clearance of the virus by the host immune system. Dendritic cells (DCs) are the most efficient inducers of immune responses; they are capable of triggering productive immunity and maintaining the state of tolerance to self- and non-self antigens. During the past decade, multiple research groups have focused on DCs, in hopes of …


Inflammasomes In Liver Diseases, Gyongyi Szabo, Timea Csak Oct 2012

Inflammasomes In Liver Diseases, Gyongyi Szabo, Timea Csak

Gyongyi Szabo

Inflammation is a common element in the pathogenesis of most chronic liver diseases that lead to fibrosis and cirrhosis. Inflammation is characterized by activation of innate immune cells and production of pro-inflammatory cytokines IL-1alpha, IL-1beta, and TNFalpha. Inflammasomes are intracellular multiprotein complexes expressed in both parenchymal and non-parenchymal cells of the liver that in response to cellular danger signals activate caspase-1, and release IL-1beta and IL-18. The importance of inflammasome activation in various forms of liver diseases in relation to liver damage, steatosis, inflammation and fibrosis is discussed in this review. Elsevier B.V. All rights reserved.


Hypoxia And Hypoxia Inducible Factors: Diverse Roles In Liver Diseases, Bharath Nath, Gyongyi Szabo Oct 2012

Hypoxia And Hypoxia Inducible Factors: Diverse Roles In Liver Diseases, Bharath Nath, Gyongyi Szabo

Gyongyi Szabo

Hypoxia has been shown to have a role in the pathogenesis of several forms of liver disease. The hypoxia inducible factors (HIFs) are a family of evolutionarily conserved transcriptional regulators that affect a homeostatic response to low oxygen tension and have been identified as key mediators of angiogenesis, inflammation, and metabolism. In this review we summarize the evidence for a role of HIFs across a range of hepatic pathophysiology. We describe regulation of the HIFs and review investigations that demonstrate a role for HIFs in the development of liver fibrosis, activation of innate immune pathways, hepatocellular carcinoma, as well as …


Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo Oct 2012

Mitochondrial Antiviral Signaling Protein Defect Links Impaired Antiviral Response And Liver Injury In Steatohepatitis In Mice, Timea Csak, Angela Dolganiuc, Karen Kodys, Bharath Nath, Jan Petrasek, Shashi Bala, Dora Lippai, Gyongyi Szabo

Gyongyi Szabo

Mitochondrial dysfunction is a pathogenic feature of nonalcoholic steatohepatitis (NASH). NASH complicates hepatotropic viral disease. The mitochondrial antiviral signaling protein (MAVS) is the adapter of helicase receptors involved in sensing double-stranded RNA (dsRNA). We hypothesized that impaired MAVS function may contribute to insufficient antiviral response and liver damage in steatohepatitis. We identified reduced MAVS protein levels and increased MAVS association with the proteasome subunit alpha type 7 (PSMA7) in livers from mice given a methionine-choline-deficient (MCD) diet. Decreased association of MAVS with mitochondria and increased cytosolic cytochrome c indicated mitochondrial damage in steatohepatitis. In vivo administration of the synthetic dsRNA …


An Essential Role For Monocyte Chemoattractant Protein-1 In Alcoholic Liver Injury: Regulation Of Proinflammatory Cytokines And Hepatic Steatosis In Mice, Pranoti Mandrekar, Aditya Ambade, Arlene Lim, Gyongyi Szabo, Donna Catalano Oct 2012

An Essential Role For Monocyte Chemoattractant Protein-1 In Alcoholic Liver Injury: Regulation Of Proinflammatory Cytokines And Hepatic Steatosis In Mice, Pranoti Mandrekar, Aditya Ambade, Arlene Lim, Gyongyi Szabo, Donna Catalano

Gyongyi Szabo

The importance of chemokines in alcoholic liver injury has been implicated. The role of the chemokine, monocyte chemoattractant protein-1 (MCP-1), elevated in patients with alcoholic liver disease is not yet understood. Here, we evaluated the pathophysiological significance of MCP-1 and its receptor, chemokine (C-C motif) receptor 2 (CCR2), in alcoholic liver injury. The Leiber-DeCarli diet containing alcohol or isocaloric control diets were fed to wild-type (WT) and MCP-1-deficient knockout (KO) mice for 6 weeks. In vivo and in vitro assays were performed to study the role of MCP-1 in alcoholic liver injury. MCP-1 was increased in Kupffer cells (KCs) as …


Human Monoclonal Antibody Hcv1 Effectively Prevents And Treats Hcv Infection In Chimpanzees, Trevor J. Morin, Teresa J. Broering, Brett A. Leav, Barbara M. Blair, Kirk J. Rowley, Elisabeth N. Boucher, Yang Wang, Peter S. Cheslock, Michael Knauber, David B. Olsen, Steve W. Ludmerer, Gyongyi Szabo, Robert W. Finberg, Robert H. Purcell, Robert E. Lanford, Donna M. Ambrosino, Deborah C. Molrine, Gregory J. Babcock Oct 2012

Human Monoclonal Antibody Hcv1 Effectively Prevents And Treats Hcv Infection In Chimpanzees, Trevor J. Morin, Teresa J. Broering, Brett A. Leav, Barbara M. Blair, Kirk J. Rowley, Elisabeth N. Boucher, Yang Wang, Peter S. Cheslock, Michael Knauber, David B. Olsen, Steve W. Ludmerer, Gyongyi Szabo, Robert W. Finberg, Robert H. Purcell, Robert E. Lanford, Donna M. Ambrosino, Deborah C. Molrine, Gregory J. Babcock

Gyongyi Szabo

Hepatitis C virus (HCV) infection is a leading cause of liver transplantation and there is an urgent need to develop therapies to reduce rates of HCV infection of transplanted livers. Approved therapeutics for HCV are poorly tolerated and are of limited efficacy in this patient population. Human monoclonal antibody HCV1 recognizes a highly-conserved linear epitope of the HCV E2 envelope glycoprotein (amino acids 412-423) and neutralizes a broad range of HCV genotypes. In a chimpanzee model, a single dose of 250 mg/kg HCV1 delivered 30 minutes prior to infusion with genotype 1a H77 HCV provided complete protection from HCV infection, …


Cd81/Cd9 Tetraspanins Aid Plasmacytoid Dendritic Cells In Recognition Of Hcv-Infected Cells And Induction Of Ifnalpha, Shuye Zhang, Karen Kodys, Gregory Babcock, Gyongyi Szabo Oct 2012

Cd81/Cd9 Tetraspanins Aid Plasmacytoid Dendritic Cells In Recognition Of Hcv-Infected Cells And Induction Of Ifnalpha, Shuye Zhang, Karen Kodys, Gregory Babcock, Gyongyi Szabo

Gyongyi Szabo

Recognition of hepatitis C virus (HCV)-infected hepatocyes and interferon (IFN) induction are critical in antiviral immune response. We hypothesized that cell-cell contact between plasmacytoid dendritic cells (pDCs) and HCV-infected cells was required for IFNalpha induction via involvement of cell surface molecules. Co-culture of human peripheral blood mononuclear cells (PBMCs) with genotype 1a full length HCV genomic replicon cells (FL) or genotype 2a JFH-1 virus infected hepatoma cells (JFH-1), not with uninfected hepatoma cells (Huh7.5), induced IFNalpha production. Depletion of pDCs from PBMCs attenuated IFNalpha release and purified pDCs produced high levels of IFNalpha after co-culture with FL replicons or JFH-1 …


Il-1 Receptor Antagonist Ameliorates Inflammasome-Dependent Alcoholic Steatohepatitis In Mice, Jan Petrasek, Shashi Bala, Timea Csak, Dora Lippai, Karen Kodys, Victoria Menashy, Matthew Barrieau, So-Yun Min, Evelyn A. Kurt-Jones, Gyongyi Szabo Oct 2012

Il-1 Receptor Antagonist Ameliorates Inflammasome-Dependent Alcoholic Steatohepatitis In Mice, Jan Petrasek, Shashi Bala, Timea Csak, Dora Lippai, Karen Kodys, Victoria Menashy, Matthew Barrieau, So-Yun Min, Evelyn A. Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is characterized by steatosis and upregulation of proinflammatory cytokines, including IL-1beta. IL-1beta, type I IL-1 receptor (IL-1R1), and IL-1 receptor antagonist (IL-1Ra) are all important regulators of the IL-1 signaling complex, which plays a role in inflammation. Furthermore, IL-1beta maturation is dependent on caspase-1 (Casp-1). Using IL-1Ra-treated mice as well as 3 mouse models deficient in regulators of IL-1beta activation (Casp-1 and ASC) or signaling (IL-1R1), we found that IL-1beta signaling is required for the development of alcohol-induced liver steatosis, inflammation, and injury. Increased IL-1beta was due to upregulation of Casp-1 activity and inflammasome activation. The …


Lipopolysaccharide Induces And Activates The Nalp3 Inflammasome In The Liver, Michal Ganz, Timea Csak, Bharath D. Nath, Gyongyi Szabo Oct 2012

Lipopolysaccharide Induces And Activates The Nalp3 Inflammasome In The Liver, Michal Ganz, Timea Csak, Bharath D. Nath, Gyongyi Szabo

Gyongyi Szabo

AIM: To examine the activation of the Nalp3 inflammasome and its downstream targets following lipopolysaccharide (LPS)-induced stimulation in the liver. METHODS: Six-to-eight-week-old C57BL/6 chow fed mice were injected intraperitoneally with 0.5 mug/g bodyweight LPS and sacrificed 2, 4, 6, 18 or 24 h later. LPS-induced liver damage was confirmed by a biochemical assay to detect alanine aminotransferase (ALT) levels. To determine if LPS stimulation in the liver led to activation of the inflammasome, real-time quantitative polymerase chain reaction was used to evaluate the mRNA expression of components of the Nalp3 inflammasome. Enzyme-linked immunosorbent assays were used to determine the protein …


Fatty Acid And Endotoxin Activate Inflammasomes In Mouse Hepatocytes That Release Danger Signals To Stimulate Immune Cells, Timea Csak, Michal Ganz, Justin Pespisa, Karen Kodys, Angela Dolganiuc, Gyongyi Szabo Oct 2012

Fatty Acid And Endotoxin Activate Inflammasomes In Mouse Hepatocytes That Release Danger Signals To Stimulate Immune Cells, Timea Csak, Michal Ganz, Justin Pespisa, Karen Kodys, Angela Dolganiuc, Gyongyi Szabo

Gyongyi Szabo

The pathogenesis of nonalcoholic steatohepatitis (NASH) and inflammasome activation involves sequential hits. The inflammasome, which cleaves pro-interleukin-1beta (pro-IL-1beta) into secreted IL-1beta, is induced by endogenous and exogenous danger signals. Lipopolysaccharide (LPS), a toll-like receptor 4 ligand, plays a role in NASH and also activates the inflammasome. In this study, we hypothesized that the inflammasome is activated in NASH by multiple hits involving endogenous and exogenous danger signals. Using mouse models of methionine choline-deficient (MCD) diet-induced NASH and high-fat diet-induced NASH, we found up-regulation of the inflammasome [including NACHT, LRR, and PYD domains-containing protein 3 (NALP3; cryopyrin), apoptosis-associated speck-like CARD-domain containing …


Caspase-1-Dependent, Il-1ss-Mediated Alcoholic Steatohepatitis Is Ameliorated By Il-1 Receptor Antagonist Treatment In Mice, Jan Petrasek, Shashi Bala, Dora Lippai, Karen Kodys, Victoria Menashy, Matthew Barrieau, Evelyn A. Kurt-Jones, Gyongyi Szabo Jul 2012

Caspase-1-Dependent, Il-1ss-Mediated Alcoholic Steatohepatitis Is Ameliorated By Il-1 Receptor Antagonist Treatment In Mice, Jan Petrasek, Shashi Bala, Dora Lippai, Karen Kodys, Victoria Menashy, Matthew Barrieau, Evelyn A. Kurt-Jones, Gyongyi Szabo

Gyongyi Szabo

Alcoholic liver disease (ALD) is characterized by steatosis and upregulation of pro-inflammatory cytokines, including interleukin (IL)-1β. IL-1β, Type-I IL-1 receptor (IL1R1) and IL-1 receptor antagonist (IL-1Ra) are all part of the IL-1 superfamily that play a role in inflammation. IL-1β maturation is dependent on Caspase-1. Using wild-type (WT), Caspase-1-, IL-1R1- and IL-1Ra deficient mice fed with Lieber-DeCarli alcohol or control diet, we have identified that signaling mediated by the active IL-1β was required for development of alcohol-induced steatosis, inflammation and injury. Increased IL-1β was due to upregulation of Caspase-1 activity and inflammatory activation. The pathogenic role of IL-1 signaling in …


Cd81/Cd9 Tetraspanins Aid Plasmacytoid Dendritic Cells In Recognition Of Hcv-Infected Cells And Induction Of Ifnα, Shuye Zhang, Karen Kodys, Gyongyi Szabo Jul 2012

Cd81/Cd9 Tetraspanins Aid Plasmacytoid Dendritic Cells In Recognition Of Hcv-Infected Cells And Induction Of Ifnα, Shuye Zhang, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

Recognition of hepatitis C virus (HCV)-infected hepatocyes and interferon (IFN) induction are critical in antiviral immune response. We hypothesized that cell-cell contact between pDCs and HCV-infected cells was required for IFNα induction via involvement of cell surface molecules. Co-culture of human peripheral blood mononuclear cells (PBMCs) with genotype 1a full length HCV genomic replicon cells (FL) or genotype 2a JFH-1 virus infected hepatoma cells (JFH-1), not with uninfected hepatoma cells (Huh7.5), induced IFNα production. Depletion of pDCs from PBMCs attenuated IFNα release and purified pDCs produced high levels of IFNα after co-culture with FL replicons or JFH-1 infected cells. IFNα …